[Coco] (Probably stupid and newbie-ish) CoCo hardware question

[John E. Malmberg]

On 6/26/2012 1:42 PM, Arthur Flexser wrote:
> Frank, that's the first time I've heard that explanation for why the
> CoCo 3 runs in all-RAM mode.  (That Tandy had rights to use, but not
> modify, the Microsoft ROMs.)  It seems very plausible to me.  Do you
> know this for a fact, or is it just a reasonable conjecture?

I always assumed that it was done because that was the easiest way to 
extend BASIC beyond the DISK BASIC ROM.

Both the BASIC and EXTENDED BASIC ROMs use a "patch" table in RAM that 
allows them to be extended.

That same patch table allows ROM Extended Color Disk Basic to run in ROM 
under the FLEX-09 using the FLEX-09 keyboard and screen I/O on a Color 
Computer I/II.

Regards,
-John
wb8tyw at qsl.network
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